For millennia, people around the world have used human excreta on fields as fertilizer, making good use of the energy and nutrients it contains, such as nitrogen, potassium and phosphorus.

Today, the same principle is used in the application of sewage sludge to agricultural fields. After sewage is processed to extract and clean wastewater, what’s left is a semi-solid mass known as biosolids. Good-quality, uncontaminated biosolids are applied to fields around the world, especially in Europe and Japan. But fertilizing fields with biosolids must be done with great care, because biosolids can contain pathogens, heavy metals, industrial chemicals, pharmaceuticals and so on.

Biosolids can also be used for forest remediation, to fill landfill sites and for urban landscaping. They are a useful feedstock for biodigesters or can be incinerated for heat recovery and electricity generation. Biosolids can even be used as a building material, such as for pavement materials or building bricks.

Healthy people in a healthy environment

Good health and well-being require a clean and harmonious environment where physical, psycho - logical, social and aesthetic factors are all given their due importance. These factors are affected by actions and choices which can secure considerable health benefits. The environment is thus not only important for its own sake, but as a resource for better living conditions and well-being.

What we’ve agreed: the Convention on the Rights of the Child and the Millennium Development Goals

Green savings

What young people want

Water – the key to life

The air we breathe

Safer, quieter towns and cities of the future – reclaiming the streets